(HealthDay)—Variants of a gene are associated with overweight and obesity in psychiatric patients taking drugs that induce weight gain, as well in the general population, according to a study published online Aug. 7 in ...

Scientists from Harvard Medical School and the CSIR-Centre for Cellular and Molecular Biology in Hyderabad, India, provide evidence that modern-day India is the result of recent population mixture among divergent demographic ...

New research into the fight against Dengue, an insect-borne tropical disease that infects up to 390 million people worldwide annually, may influence the development of anti-viral therapies that are effective against all four ...

There are some smells we all find revolting. But toward a handful of odors, different people display different sensitivities—some can smell them, while some can't, or some find them appealing, while others don't. A pair ...

(Medical Xpress)—A new study led by University of Pennsylvania researchers involves a classic case of evolution's fickle nature: a genetic mutation that protects against a potentially fatal infectious disease also appears ...

Researchers from Dartmouth's Institute for Quantitative Biomedical Sciences (iQBS), the Center for Integrative Biomedical Sciences, and the Center for Genomic Medicine at the Geisel School of Medicine are studying the unknown ...

Children born as a result of assisted reproduction (ART) are at no greater risk of cancer than children born spontaneously in the general population, according to results of one of the largest ever cohort studies of ART children. ...

World population

The term world population commonly refers to the total number of living humans on Earth at a given time. As of 29 July 2009, the Earth's population is estimated by the United States Census Bureau to be 6.774 billion. The world population has been growing continuously since the end of the Black Death around 1400. There were also short term falls at other times due to plague, for example in the mid 17th century (see graph). The fastest rates of world population growth (above 1.8%) were seen briefly during the 1950s then for a longer period during the 1960s and 1970s (see graph). According to population projections, world population will continue to grow until around 2050. The 2008 rate of growth has almost halved since its peak of 2.2% per year, which was reached in 1963. World births have levelled off at about 134-million-per-year, since their peak at 163-million in the late 1990s, and are expected to remain constant. However, deaths are only around 57 million per year, and are expected to increase to 90 million by the year 2050. Since births outnumber deaths, the world's population is expected to reach about 9 billion by the year 2040.